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Showing papers in "Russian Chemical Bulletin in 1994"


Journal ArticleDOI
TL;DR: In this article, a strategy of organic synthesis for a new class of inorganic compounds, i.e., dinitramide and its metal, ammonium, and substituted ammonium salts, was developed for β-substituted derivatives of N-alkyl-N-nitrotoluenesulfonamides with bases.
Abstract: A strategy of organic synthesis has been developed for a new class of inorganic compounds,viz., dinitramide and its metal, ammonium, and substituted ammonium salts. The basic concepts have been tested in model reactions of β-substituted derivatives ofN-alkyl-N-nitrotoluenesulfonamides with bases and have been confirmed by the decyanoethylation ofN,N-dmitro-β-aminopropionitrile taken as an example.

38 citations


Journal ArticleDOI
TL;DR: In this article, the fundamental and applied aspects of liquid separation by means of pervaporation through polymeric membranes are considered and a review gives the state of the art as well as prospects of development of this branch of membrane science and technology.
Abstract: Fundamental and applied aspects of liquid separation by means of pervaporation through polymeric membranes are considered. The review gives the state of the art as well as prospects of development of this branch of membrane science and technology.

38 citations


Journal ArticleDOI
TL;DR: In this article, the physicochemical properties of dinitramide HN(NO2)2 with uni-and bivalent metals of groups I, II, VII, and VIII of the Periodic Table are considered.
Abstract: The preparation and physicochemical properties of salts of dinitramide HN(NO2)2 with uni- and bivalent metals of groups I, II, VII, and VIII of the Periodic Table are considered.

37 citations


Journal ArticleDOI
TL;DR: In this article, the presence of copper ions leads to broadening of the absorption band associated with the silver sols and shifts it to the UV region, which is due to the transfer of electrons from copper to silver.
Abstract: Colloidal copper has been obtained by γ-irradiation of aqueous solutions of copper (II) perchlorate in the presence of alcohol and polyethyleneimine (PEI). The sols are spherical particles about 4 nm in diameter, which are quickly oxidized by oxygen or other oxidants. When CuII is not entirely incorporated into the complex with PEI, disproportionation of CuI aqua complexes formed affords the metal, along with Cu2O. Reduction of the PEI complex of CuI by hydrated electrons gives only colloidal copper. The copper ions can be reduced on the surface of silver sols. Optical parameters of the resulting bimetallic particles have been studied. The presence of copper ions leads to broadening of the absorption band associated with the silver sols and shifts it to the UV region, which is due to the transfer of electrons from copper to silver. Three copper monolayers are enough to cause plasmon absorption of colloidal copper.

33 citations


Journal ArticleDOI
TL;DR: In this paper, the formation of hydroxyl radicals and their participation in hydrocarbon oxidation by a H2O2-vanadium complex-2-pyrazinecarboxylic acid reagent has been obtained by the spin trap method and kinetically, by competitive oxidation of a benzenealiphatic alcohol mixture.
Abstract: Evidence for the formation of hydroxyl radicals and their participation in hydrocarbon oxidation by a H2O2-vanadium complex-2-pyrazinecarboxylic acid reagent has been obtained by the spin trap method and kinetically, by competitive oxidation of a benzenealiphatic alcohol mixture.

29 citations


Journal ArticleDOI
TL;DR: A number of porphyrin derivatives based on hematoporphrin, 5,10,15,20-tetrasubstituted porphrin derivatives, phthalocyanines, and naphthalocynines were prepared either as low-molecular compounds or bonded with methoxypoly(ethylene glycol) or attached to silica of low surface area as mentioned in this paper.
Abstract: A number of porphyrin derivatives based on hematoporphyrin, 5,10,15,20-tetrasubstituted porphyrins, phthalocyanines, and naphthalocyanines were prepared either as low-molecular compounds or bonded with methoxypoly(ethylene glycol) or attached to silica of low surface area. The low-molecular weight and the polymer-bonded porphyrins exhibit comparable triplet lifetimes and activities in the photosensitized formation of singlet oxygen. For photoninduced processes, the monomeric state of sensitizers is fundamentally important. The porphyrins have been investigated as sensitizers for photooxidation of thiolates and sulfides, which occursvia singlet oxygen, and, therefore, is much more efficient than the corresponding catalytic dark oxidation. Polymer-bonded porphyrins and long-wavelength absorbing naphthalocyanines incorporated in liposomes exhibitin vivo high accumulation in tumor tissues. Under irradiation, singlet oxygen is produced, and efficient phototherapeutic effects are observed, which may be used for photodynamic cancer therapy.

26 citations


Journal ArticleDOI
TL;DR: The structure of the zirconium phosphate was determined by X-ray diffraction analysis as discussed by the authors, and its structure was shown to be stable with respect to temperature and humidity.
Abstract: The zirconium phosphate [Zr(HPO4)(PO4)F2] · 1.5H2en was prepared, and its structure was determined by X-ray diffraction analysis.

22 citations


Journal ArticleDOI
TL;DR: The dinitramide anion shows ambident properties and its reactions with alkylating reagents give rise to N- or O-alkylated products or their mixtures as mentioned in this paper.
Abstract: The dinitramide anion shows ambident properties. Its reactions with alkylating reagents give rise to N- or O-alkylated products or their mixtures. The reactions of alkylated products with bases were studied.

22 citations


Journal ArticleDOI
TL;DR: In this article, the SA phase of liquid crystalline complexes of the type [ML(LH)2](NO3)2, where LH=C7H15O-C6H3(OH)CH=N-C18H37 and M=Gd, Dy, and La, have been obtained.
Abstract: Liquid crystalline complexes of the type [ML(LH)2](NO3)2, where LH=C7H15O-C6H3(OH)CH=N-C18H37 and M=Gd, Dy, and La, have been obtained. All of them exhibit the SA phase and have high magnetic birefringence constants due to the association of the complexes in solution. In the case of the dysprosium derivative, the effect is much stronger (four orders of magnitude greater than the usual value) because of the high magnetic anisotropy of the particles of the complex.

22 citations


Journal ArticleDOI
TL;DR: The authors have developed a general method for the direct addition of amino acids and dipeptides of various structures to fullerene C{sub 60} that involves the amino group.
Abstract: The authors have developed a general method for the direct addition of amino acids and dipeptides of various structures to fullerene C{sub 60}. In all cases the addition involves the amino group. The reaction proceeds when the solutions of fullerene and an amino acid (or dipeptide) are mixed at 50-100 {degrees}C. The fullerene derivatives of the following amino acids and dipeptides have been obtained: glycine, p-aminobenzoic acid, {omega}-aminocaproic acid, L-proline, L-alanine, L-alanyl-Lalanine, D,L-alanyl-D,L-alanine, glycyl-L-valine. The adduct of methyl L-ananinate with C{sub 60} was also prepared.

21 citations



Journal ArticleDOI
TL;DR: In this paper, a catalytic system based on phosphine complexes of palladium was developed for synthesizing propionic acid (monocarbonylation) and alternating (1∶1) ethylene-carbon monoxide copolymers (polycarbonylation).
Abstract: Catalytic systems based on phosphine complexes of palladium have been developed for synthesizing propionic acid (monocarbonylation) and alternating (1∶1) ethylene-carbon monoxide copolymers,i.e., polyketones (polycarbonylation).m-(Diphenylphosphino)benzenesulfonic acid or its sodium salt were used as ligands. Monocarbonylation proceeds at atmospheric pressure in dioxane or acetic acid solvents. Under high pressure, the reaction pathway can change from monocarbonylation, which occurs in the presense of the sodium salt of the ligand, to polycarbonylation when the sodium ion at the sulfo group is completely replaced by a proton. This change in reaction selectivity is observed when the process is performed in acetic acid. When the ligand is present both in the acid and the neutral form, products of di- and oligocarbonylation are formed along with propionic acid and the polyketone. These products were characterized by1H and13C NMR spectra as alternating keto acids C2H5(COCH2CH2) n COOH, wheren=1÷3. Kinetic equations were derived for the selective synthesis of propionic acid and polyketones.

Journal ArticleDOI
TL;DR: In this paper, the length of a polymethine chain of symmetrical cyanine dyes is related to their spectral-luminescent properties depending on the electron-donor character of the heterocycles and the nature of the solvent.
Abstract: The general characteristics that relate the length of the polymethine chain of symmetrical cyanine dyes to their spectral-luminescent properties depending on the electron-donor character of the heterocycles and the nature of the solvent are formulated. For various types of symmetrical cyanines, the Stokes shifts decrease with the elongation of the polymethine chain due to weakening of the vibronic interactions. The vinylene shifts of the band maxima are essentially constant and fall within the range 100 to 130 nm depending on the nature of the heterocycles and the solvent. When the polymethine chain elongates the fluorescence quantum yields first increase and then decrease. The greater the effective length of the heterocycle the stronger the decrease. The fluorescence decay occurring when the polymethine chain gets longer is associated with intensification of the internal conversion. For symmetrical cyanines, the changes in the shapes of the electronic bands (their width, asymmetry, excess, and fine structure) as the chain elongates are governed by the competing effects of the vibronic and intermolecular interactions. The former decrease as the chain lengthens, causing the narrowing of the absorption bands for the lower vinylogs. On the other hand, the latter increase as chain lengthens, which leads to broadening of the bands for the higher vinylogs. The higher the solvent nucleophilicity and the greater the deviation of the electron-donor ability of the heterocycle from the average value the greater the broadening. Any elongation of the polymethine chain of symmetrical cyanines causes only narrowing of the bands and an increase in the asymmetry, excess, and structuring in the fluorescence spectra, which, unlike the absorption spectra, is independent of the electron-donor character of the heterocycles and the nature of the solvent. These effects are caused by the fact that, in contrast to absorption, changes in the shape of emission bands with increasing chain length are governed predominantly by vibronic rather than by intermolecular interactions.

Journal ArticleDOI
TL;DR: In this article, it was shown that in the covalent state of dinitramide, the proton is bound to the central nitrogen atom (HN(NO2)2) and the two oxygen atoms of both nitro groups.
Abstract: IR and UV spectroscopic studies of dinitramide have shown that in the covalent state it exists as two forms. In one of these forms, the proton is bound to the central nitrogen atom (HN(NO2)2). In the other form, the proton is equally bound to the two oxygen atoms of both nitro groups.

Journal ArticleDOI
TL;DR: Dinitramide readily adds to acrolein, methyl vinyl ketone, and phenyl vinyl kone, but not to acrylonitrile or methyl acrylate as mentioned in this paper.
Abstract: Dinitramide readily adds to acrolein, methyl vinyl ketone, and phenyl vinyl ketone, but not to acrylonitrile or methyl acrylate. Treatment of dinitro compounds (O2N)2NCH2CH2COR (R = H, Me, Ph, OMe) with bases results in dinitramide salts in 66–83 % yields.

Journal ArticleDOI
TL;DR: The reaction of 15N-labeled chloroacetamidoxime with cyanoguanidine showed that the formation of the oxadiazole ring occurs via the elimination of the amino group from the amidoxime fragment.
Abstract: The reaction of amidoximes with cyanoguanidine in the presence of Lewis acids affords 3-substituted 5-guanidino-1,2,4-oxadiazoles. A study of the reaction of15N-labeled chloroacetamidoxime with cyanoguanidine showed that the formation of the oxadiazole ring occursvia the elimination of the amino group from the amidoxime fragment. 1,2,4-Oxadiazoles bearing the imidazole or pyrimidine moiety were synthesized.

Journal ArticleDOI
TL;DR: Asymmetric catalysis of metal carbene transformations with unique chiral dirhodium(II) carboxamides provides highly enanti-lective and diastereoselective syntheses via cyclopropanation, cyclop-enation, and carbon-hydrogen insertion reactions of diazoesters and diazoamides as mentioned in this paper.
Abstract: Asymmetric catalysis of metal carbene transformations with unique chiral dirhodium(II) carboxamides provides highly enantioselective and diastereoselective synthesesvia cyclopropanation, cyclopropenation, and carbon-hydrogen insertion reactions of diazoesters and diazoamides. Constructed from a dirhodium(II) core with bridging pyrrolidone, oxazolidinone, or imidazolidinone ligands, these catalysts are especially effective for intramolecular transformations that occur in high yield with greater than 90 % enantiomeric excess (ee) and high diastereocontrol.

Journal ArticleDOI
TL;DR: The C60·2S8 complex as mentioned in this paper was prepared by reaction of buckminsterfullerene C60 with sulfur in trichloroethylene and its single-crystal X-ray structure was studied at room temperature.
Abstract: The C60·2S8 complex was prepared by reaction of buckminsterfullerene C60 with sulfur in trichloroethylene and its single-crystal X-ray structure was studied at room temperature. Crystals of this compound are monoclinic, space groupC 2/c, a=20.90(1),b=21.10(1),c=10.537(9) A, β=111.29(7)°,Z=4,d calc=1.89 g·cm−3. The crystal structure of the C60·2S8 complex consists of packed fullerene molecules that form hexagonal channels along thec axis with eight-membered crown-shaped S8 cyclic molecules inside the channels. The distances between the centers of neighboring fullerene molecules are 10.036(7), 10.636(7), and 10.537(9) A. Each C60 molecule is linked to eight S8 molecules with ten shortened intermolecular contacts C...S 3.41(1)–3.52(2) A. The average values of the C=C and C-C bond lengths are 1.32(3) and 1.47(3) A, which attest to a significant degree of localization of electron density in the c60 molecule.

Journal ArticleDOI
TL;DR: In this paper, the results of the use of a flow cytometer of standard design for the anaysis of milk microflora and for an AIDS immunoassay by latex agglutination are given.
Abstract: Numerical methods for solving the reverse problem of light scattering for single particles and a variety of experimental results have been reviewed. In particular, the two-dimensional Mie scattering method for the estimation of sizes and refractive indices of single particles has been developed. The method of triple two-dimensional Mie scattering has been elaborated, which extends the range of particle sizes with correct solutions of the reverse light scattering problem. The flying light scattering indicatrix method, which allows the estimation of the parameters of spherical particles, is presented. The results of the use of a flow cytometer of standard design for the anaysis of milk microflora and for an AIDS immunoassay by latex agglutination are given. The design of a scanning flow cytometer is considered. The results of measuring the light scattering from polystyrene latex particles are given.

Journal ArticleDOI
TL;DR: The structures of complexes formed during the transformation of amidoximes into 1,2,4-oxadiazoles by the action of nitriles in the presence of zinc chloride and HCl were studied by 15N NMR spectroscopy as discussed by the authors.
Abstract: The structures of complexes formed during the transformation of amidoximes into 1,2,4-oxadiazoles by the action of nitriles in the presence of zinc chloride and HCl were studied by15N NMR spectroscopy.

Journal ArticleDOI
TL;DR: In this article, a new synthetic method for the preparation of 15N-labeled nitriles from nonlabeled Nitriles is proposed, which can be used to synthesize 15N nitrate.
Abstract: A new synthetic method for the preparation of15N-labeled nitriles from nonlabeled nitriles is proposed.

Journal ArticleDOI
TL;DR: In this paper, simple and efficient methods for the synthesis of trans-3-fluoroalkyl-2-aziridinyl ketones from polyfluorinated α,β-enones have been developed.
Abstract: Simple and efficient methods for the synthesis oftrans-3-fluoroalkyl-2-aziridinyl ketones from polyfluorinated α,β-enones have been developed

Journal ArticleDOI
TL;DR: In this article, the effect of the anion of the supporting electrolyte and the anode material on the performance of anodic oxidation of styrene in methanol has been studied.
Abstract: Anodic oxidation of styrene (1) in methanol and the effect of the anion of the supporting electrolyte and of the anode material on this process have been studied. The most efficient conversion of1 into (1,2-dimethoxyethyl)benzene (2) occurs when the electrolysis is carried out with a platinum anode and with potassium fluoride or tetrabutylammonium tetrafluoroborate as the supporting electrolyte. Cleavage of the C-C σ bond in2 to give benzaldehyde dimethylacetal (3) is the most efficient at a graphite anode in the presence of sodium tosylate.

Journal ArticleDOI
TL;DR: In this paper, the kinetics of decomposition of 15 difluoroamino compounds with NF2 groups at primary, secondary, and tertiary carbon atoms in the liquid state were investigated.
Abstract: The kinetics of decomposition of 15 difluoroamino compounds with NF2 groups at primary, secondary, and tertiary carbon atoms in the liquid state was investigated. Activation energies (Ea) for all of the compounds were in the interval 100–120 kJ · mol−1. The reaction rate does not depend on the electronic effects of the substituents and decreases only in the case of steric shielding of the NF2 group. ForN-difluorobenzylamine it was shown that the gas-phase elimination of HF is characterized byE = 176 kJ·mole−1, while the rate of decomposition in a solution depends on the dielectric constant of the medium. Based on the results obtained, a mechanism for liquid-phase decomposition, which involves heterolysis of the N-F bonds, is suggested.

Journal ArticleDOI
TL;DR: In this paper, the annelation of a pyridine ring to a pyrimidine ring was suggested and a method for annelating pyridines to pyrimidines was proposed.
Abstract: New methods for annelation of a pyridine ring to a pyrimidine ring were suggested. Substituted 8H-pyrido[2,3-d]pyrimidin-5-ones (8a-f) were synthesized by the interaction of 2,6-disubstituted 4-amino-5-acetylpyrimidines (1–4) with formamide or acetamide acetals followed by cyclization under the action of sodium methoxide in methanol. 2,4-Disubstituted 7-phenyl-8H-pyrido[2,3-d]pyrimidin-5-ones (11a-c) were prepared by the reaction of 2,6-disubstituted 5-acetyl-4-benzoylaminopyrimidines (10a-c) with MeONa in boiling BuOH.

Journal ArticleDOI
TL;DR: In this paper, the catalytic activity of MIMII2O3 spinel-type complex oxides (MI = Cu, Ni, Mn, Zn, Mg, Co, MII = Co, Cr, Al) in the oxidation of CO and ethylbenzene has been investigated.
Abstract: The catalytic activity of MIMII2O3 spinel-type complex oxides (MI = Cu, Ni, Mn, Zn, Mg, Co, MII = Co, Cr, Al) in the oxidation of CO and ethylbenzene has been investigated. The Co-containing catalysts were more active than the Cr- and Al-containing catalysts. The nature of the cation influenced the catalytic activity. Higher activities were observed for the catalysts containing two transition elements. A correlation between the catalytic and adsorption properties was established.

Journal ArticleDOI
TL;DR: In this article, the effect of the parameters of the electric arc (helium pressure, current and voltage, clearance between electrodes) and of the setup design (arrangement of electrodes, distance between the arc and the cooling surface, temperature of the soot condensation surface) on the yield of fullerenes has been studied.
Abstract: The effect of the parameters of the electric arc (helium pressure, current and voltage, clearance between electrodes) and of the peculiarities of the setup design (arrangement of electrodes, distance between the arc and the cooling surface, temperature of the soot condensation surface) on the yield of fullerenes has been studied. Conditions for producing soot with a C60 and C70 content up to 43% (toluene extract) have been found.

Journal ArticleDOI
TL;DR: A series of new heteronuclear complexes of a ferrocene-containing Schiffs base (LH) with NiII, PdII, VIVO, and FeIII as the central atoms has been obtained as discussed by the authors.
Abstract: A series of new heteronuclear complexes of a ferrocene-containing Schiffs base (LH) with NiII, PdII, VIVO, and FeIII as the central atoms has been obtained. PdL2, VOL2 FeL2Cl, and [FeL2]2O complexes manifest liquid-crystalline properties and NiL2 is nonmesomorphic. The structures of the complexes synthesized have been established by magnetic measurements and IR and ESR spectroscopy. All of them except PdL2 are paramagnetic. The antiferromagnetic exchange interactions have been observed in the FeIII complexes. The correlation of liquid-crystalline properties with the geometry of the chelate centers is discussed.

Journal ArticleDOI
TL;DR: A triterpenoid glycoside, (20S,22S,23R,24S)-3β,22,23-trihydroxy-3-O-[O-(β-D-glucuronopyranosyl)-(1→6)-(β-d-glocopyraniumyl)]-14-nor-24-methyllanost-8(9)-en-31-oic acid (ulososide A), has been isolated from the sponge Ulosa sp. and characterized.
Abstract: A new triterpenoid glycoside, (20S,22S,23R,24S)-3β,22,23-trihydroxy-3-O-[O-(β-D-glucuronopyranosyl)-(1→6)-(β-D-glucopyranosyl)]-14-nor-24-methyllanost-8(9)-en-31-oic acid (ulososide A), has been isolated from the sponge Ulosa sp. and characterized.

Journal ArticleDOI
TL;DR: In this paper, the catalytic activity of MIMIIO3] perovskite-type complex oxides (MI = La, Y, Nd, Yb; MII = Co, Mn, Ni) in the oxidation of CO, propylene, benzene, ethylbenzene,o-xylene, and ethyl acetate was investigated.
Abstract: The catalytic activity of MIMIIO3] perovskite-type complex oxides (MI = La, Y, Nd, Yb; MII = Co, Mn, Ni) in the oxidation of CO, propylene, benzene, ethylbenzene,o-xylene, and ethyl acetate was investigated. The Co-containing catalysts were shown to be more active in the oxidation than the Mn-containing catalysts. A relationship between the catalytic and adsorption properties was established.